A police car had pulled up on the street behind and below–us, and it was emitting that deep guttural sound that signals that the officers inside want to talk to you. One leaned out of the driver-side window. “Everybody get down now,” he called to us. He watched us dismount. “Thank you.” He drove off.

We had been standing on the metal scaffolding outside the Leo Koenig gallery on West 23rd Street, perched five or ten feet in the air, catching glimpses of artists MPA and Amapola Prada Revolution as they staged their Performa piece, Two Marks in Rotation, inside. (Our awkward photographs of the event are above.)

Gallerist had arrived about five minutes before the start time, 6:30 p.m., and found a dense line of people stretching down the street toward 10th Avenue. Only about half of that crowd, a few dozen people, made it inside the space, sitting on the floor. The rest of us–including Rhizome director Lauren Cornell and performance artist Ryan McNamara–were locked outside.

Few of those outside departed. Instead, they found spots around the windows. One woman hopped onto a friend’s shoulders. Kim Bourus, the director of Higher Pictures, who shows MPA’s work, gamely made her way back up the scaffolding, and was joined by a few others. The police never returned.

Inside, we could see the two women wielding metal scaffolding poles. They grabbed either end of one piece and pushed against each other above the audience, leaning into one another as if fighting out a reverse tug of war. Later, they clanged their poles around the border of the audience, tracing the confines of the gallery. Their motions became more violent, as Amapola Prada Revolution, in a red tank-top, began attacking the white wall with ferocious jabs that sent white dust into the air.

From the outside, the action felt strangely tranquil. MPA has played with this inside-outside dynamic before. Two years ago, she shattered a sheet of glass at Cleopatra’s in Greenpoint, disrobed and laid down on those shards for a few moments, tempting injury. People watched on the street and in the gallery in dead silence.

At Koenig, the mood was calmer and looser. There were a few smiles inside the gallery as the women ushered their crowd about the space, with their metal poles. Outside, people smoked and discussed the piece. Some narrated for the shorter among us, and for those unable to find a vantage point. “Now MPA is banging her pole on the ground,” one man said. “And again. And again.”

We missed the visceral thrill of the piece, catching only bits and pieces of the action, but, for tonight at least, that seemed perfectly fine. Sometimes, with performance art, you catch a piece at precisely the right moment, and it clicks in your memory. Other times you arrive late–or not early enough.

If we believe that the medium of performance still has some life left in it, such disappointments, such missed opportunities, are a necessity: they make the highs higher. That, at least, was our rationalization last night. It didn’t hurt that we could also see a massive video camera inside the gallery, documenting the action.